Typically, staircases are completely produced on site with the various wood components being cut to size as the staircase is progressively erected on site.
Also, it has been proposed to completely assemble a staircase in the factory such that a pre-assembled staircase is delivered to the construction site for direct and easy installation thereat. Such a modular staircase is disclosed in the Canadian Application No. 2,149,981 naming Raymond Couture as inventor and laid-open for public inspection on Nov. 24, 1995.
In Canadian Application No. 2,276,988 also naming Raymond Couture as inventor and laid-open for public inspection on Dec. 30, 1999, a modular staircase is proposed that includes a permanent framing made of metallic stringers and vertically extending step supports that are secured along the stringers. Each step support includes upper and front flanges adapted to be secured respectively to a tread and to a riser of each step of the staircase. If the staircase has a partly exposed side, various decorative or finishing wooden components, including treads, risers, false or decorative stringers, mouldings, etc., are provided to cover any exposed structural metallic framework and particularly the stringers.
Furthermore, PCT Patent Publication No. WO 2005/090705-A1 published on Sep. 29, 2005 in the name of Raymond Couture, discloses staircases that are constructed of modular stringers for the on-site installation of the staircases in a residential, commercial or industrial setting. Kits for erecting the staircases include matingly or cooperatively coupling step support units defining the staircase stringers, a set of steps adapted to be mounted thereon, as well as various finishing elements and modules to provide a finished look to the completed staircases. The staircases include self-supporting staircases, linear staircases, curling or spiralling staircases and adjustable variations thereof.
Finally, PCT Patent Publication No. WO 2009/021321-A1 published on Feb. 19, 2009 in the name of Case-Modular Stair Systems Inc., discloses a stairway system, kit and method for assembling the kit. The system includes pre-fabricated components such as steps, stringers, decorative mouldings and panels or boards, etc. The kit comprises a step module and an adjacent step module, the step module comprising a riser and a tread, the riser being adapted to abut the tread on a first side thereof and being adapted to define a fastener-mating portion on a second side thereof. The tread is adapted to be secured atop the riser on one side thereof. The adjacent step module comprises a riser and a tread, the adjacent step module being adapted to be assembled with the step module by engaging a fastener with the fastener-mating portion of the step module and securing the fastener to the tread of the adjacent step module to secure the two step modules together. A stringer is adapted to be disposed on a wall where the step module is adjacent to the wall. Also, a finishing board is provided for mounting on the exposed side of the stairway.
In spite of these various devices, there remains a need for a structural stringer having an aesthetic look, when exposed, typically for use in a modular stairway system, generally in the form of a kit, which can be assembled to erect a stairway on site.